/*
 * Copyright (C) 2009 The Android Open Source Project
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

#ifndef PINYINIME_INCLUDE_SPELLINGTABLE_H__
#define PINYINIME_INCLUDE_SPELLINGTABLE_H__

#include <stdlib.h>
#include "./dictdef.h"

namespace ime_pinyin
{

#ifdef ___BUILD_MODEL___

	const size_t kMaxSpellingSize = kMaxPinyinSize;

	typedef struct {
		char str[kMaxSpellingSize + 1];
		double freq;
	} RawSpelling, *PRawSpelling;

	// This class is used to store the spelling strings
	// The length of the input spelling string should be less or equal to the
	// spelling_size_ (set by init_table). If the input string is too long,
	// we only keep its first spelling_size_ chars.
	class SpellingTable
	{
	private:
		static const size_t kNotSupportNum = 3;
		static const char kNotSupportList[kNotSupportNum][kMaxSpellingSize + 1];

		bool need_score_;

		size_t spelling_max_num_;

		RawSpelling *raw_spellings_;

		// Used to store spelling strings. If the spelling table needs to calculate
		// score, an extra char after each spelling string is the score.
		// An item with a lower score has a higher probability.
		char *spelling_buf_;
		size_t spelling_size_;

		double total_freq_;

		size_t spelling_num_;

		double score_amplifier_;

		unsigned char average_score_;

		// If frozen is true, put_spelling() and contain() are not allowed to call.
		bool frozen_;

		size_t get_hash_pos(const char *spelling_str);
		size_t hash_pos_next(size_t hash_pos);
		void free_resource();
	public:
		SpellingTable();
		~SpellingTable();

		// pure_spl_size is the pure maximum spelling string size. For example,
		// "zhuang" is the longgest item in Pinyin, so pure_spl_size should be 6.
		// spl_max_num is the maximum number of spelling strings to store.
		// need_score is used to indicate whether the caller needs to calculate a
		// score for each spelling.
		bool init_table(size_t pure_spl_size, size_t spl_max_num, bool need_score);

		// Put a spelling string to the table.
		// It always returns false if called after arrange() withtout a new
		// init_table() operation.
		// freq is the spelling's occuring count.
		// If the spelling has been in the table, occuring count will accumulated.
		bool put_spelling(const char *spelling_str, double spl_count);

		// Test whether a spelling string is in the table.
		// It always returns false, when being called after arrange() withtout a new
		// init_table() operation.
		bool contain(const char *spelling_str);

		// Sort the spelling strings and put them from the begin of the buffer.
		// Return the pointer of the sorted spelling strings.
		// item_size and spl_num return the item size and number of spelling.
		// Because each spelling uses a '\0' as terminator, the returned item_size is
		// at least one char longer than the spl_size parameter specified by
		// init_table(). If the table is initialized to calculate score, item_size
		// will be increased by 1, and current_spl_str[item_size - 1] stores an
		// unsinged char score.
		// An item with a lower score has a higher probability.
		// Do not call put_spelling() and contains() after arrange().
		const char *arrange(size_t *item_size, size_t *spl_num);

		float get_score_amplifier();

		unsigned char get_average_score();
	};
#endif  // ___BUILD_MODEL___
}

#endif  // PINYINIME_INCLUDE_SPELLINGTABLE_H__
